/* 从标准输入读命令并执行 */
#include "apue.h"
#include <sys/wait.h>

static void sig_int(int); /* our signal-catching function */

int main(void)
{
	char 	buf[MAXLINE];
	pid_t 	pid;
	int 	status;
	
	if (signal(SIGINT, sig_int) == SIG_ERR)
		err_sys("signal error");
		
	printf("%% ");
	while (fgets(buf, MAXLINE, stdin) != NULL) {
		if (buf[strlen(buf) - 1] == '\n')
			buf[strlen(buf) - 1] = 0; /* replace newline with null */
			
		if ((pid = fork) < 0) {
			err_sys("fork error");
		} else if (pid == 0) { /* child */
			execlp(buf, buf, (char *)0);
			err_ret("couldn't execute: %s", buf);
			exit(127);
		}
		
		/* parent */
		if ((pid = waitpid(pid, &status, 0)) < 0)
			err_sys("waitpid error");
		printf("%% ");	
	}
	exit(0);
}

void sig_int(int signo)
{
	printf("interrup\n%% ");
}